Remove the kale leaves from the stalks, discarding the stalks. Rinse the kale leaves and dry them thoroughly.

Thinly slice the onion and garlic and finely dice the sausage. Heat the oil in a large nonstick skillet that has a lid, over a medium-high heat. Add the onion and chorizo and cook until the onions are softened, 3-4 minutes. Meanwhile, chop the kale into ½ inch pieces.

Add the garlic to the skillet and cook, stirring, 1 minute more. Add kale and stock and cook until the kale is wilted, 3 minutes. Season the fish with the salt and pepper. Arrange the fish on top of the greens in the skillet, lower the heat to medium-low, cover, and cook until the fish is opaque and flakes easily with a fork, 10 minutes. Place a piece of fish in each of four shallow serving bowls. Divide the greens and broth among the plates and
serve.